code: def tile(cls, op):
      # Isolate ops on cpu from subsequent ops on gpu
      yield
      out_chunks = []
      for c in op.input.chunks:
          chunk_op = op.copy().reset_key()
          out_chunk = chunk_op.new_chunk([c], **c.params)
          out_chunks.append(out_chunk)
  
      new_op = op.copy().reset_key()
      out = op.outputs[0]
      return new_op.new_tileables(
          op.inputs,
          chunks=out_chunks,
          nsplits=op.inputs[0].nsplits,
          **out.params,
      )
  
file_path: mars/mars/dataframe/base/core.py
imports: from ...serialization.serializables import KeyField
  from ..operands import DataFrameOperand, DataFrameOperandMixin
  from ..core import DATAFRAME_TYPE, SERIES_TYPE
label_desc: Use image node_id 4 for calling the DataFrameDeviceConversionBase obj's underlying member method code with example usage: obj.tile(cls, op) and returns: new_op